Valve apparatus for internal combustion engines



' H. T. M. RICE VALVE APPARATUS FOR INTERNAL COMBUSTION ENGINES 2Sheets-Sheet 1 July 6, 1965 Filed April 15, 1964 lia- : j;IIIIIIIIIIIIIIIIIIIIIII6 a: 5 jn 18 25 fia- 2o 4/ 3 n 53 A 4/ l7 ,4Milli/[1% 42 I 1 25 E? I V 3 a a3 25 4 i 1 i 2. L 54 I] 41 I I INVENTOR.V I HEMPY TUMOR/c1; W Si-7"; m J "d5 July 6, 1965 H. T- M. RICE3,192,913

VALVE APPARATUS FOR INTERNAL COMBUSTION ENGINES Filed April 15, 1964 2Sheets-Sheet 2 1210. 6. I ia. 7.

INVENTOR.

.HLCMQY Z M. 8/65 United States Patent 3,192,913 VALVE APPARATUS FQRENTERNAL 0MBUSTION ENGINES Henry T. M. Rice, San Gabriel, Calif assignorto Qhlsson dz Rice, Inc., Los Angeles, Caiif., a corporation of(Ialii'ornia Filed Apr. 13, 1964, Ser. No. 359,375 9 Claims. (Cl. 123-73) The present invention relates to internal combustion engines, andmore particularly to engines utilizing crankcase compression for forcinga fuel-air mixture into the engine cylinder.

An object of the present invention is to provide an internal combustionengine embodying a crankcase fuel mixture inlet valve that opens morereadily and sooner to secure feeding of a greater fuel mixture into thecrankcase for subsequent discharge into the cylinder.

Another object of the invention is to provide an internal combustionengine embodying a crankcase fuel mixture inlet valve that enables theengine to be started more readily, operate at slower idling speeds, andoperate efliciently over a wide range of speeds.

A further object of the invention is to provide an internal combustionengine embodying a fuel mixture inlet valve element that issubstantially insensitive to sound waves or other vibration inducinginfluences of the engine that would tend to adversely affect opening andclosing of the valve element with respect to the piston positions in thecylinder. The valve opens and closes in strict conformance with thepositions of the piston and its directions of motion.

An additional object of the invention is to provide an internalcombustion engine embodying a crankcase fuel mixture inlet valve elementthat has substantially no frequency of oscillation so that it will notvibrate like a reed, but, instead, will open sooner and close morereadily in response to the positions of the piston in the cylinder, andwill not bounce from its companion seat when moved into engagementtherewith.

Yet another object of the invention is to provide an internal combustionengine embodying a crankcase fuel mixture inlet valve that minimizes thetendency of dirt, and other foreign matter, remaining in blockingposition between the valve element and its companion seat, which mightprevent full closing of the valve, and in which any dirt that might comebetween the valve and its valve seat is prevented from forestalling fullclosing of the valve.

This invention possesses many other advantages, and

has other objects which may be made more clearly ap- FIGURE 1 is alongitudinal section through a twocycle internal combustion engineembodying the invention;

FIG. 2 is an enlarged section taken along the line 2-2 on 'FIG. 1;

FIG. 3 is a section taken generally along the line 3-3 on FIG, 2;

FIG. 4 is an enlarged fragmentary section of the induction or inletvalve portion of the engine disclosed in FIG. 1;

. on FIG. 1;

ice

FIGS. 6, 7, 8 and 9 are diagrammatic views illustrating the operation ofthe engine and of its induction or inlet valve.

The internal combustion engine illustrated in the drawings is of thetwo-cycle type, including a cylinder 10 and a piston 11 recipr-ocabletherein. A wrist pin 12 is mounted in the piston and receives one end ofa connecting rod 13, the other end of which extends around a crankpin 14of a crankshaft 15 rotatably mounted in a crankcase 16 suitably securedto the cylinder 1!). Suitable ball or roller type of bearings 17 may bedisposed between the opposite portions 18, 19 of the crankshaft 15 andthe crankcase 16 itself.

A fuel-air mixture is fed from the crankcase 16 through an inlet passage20 and inlet port 21 into the cylinder 10 when the piston is near theend of its stroke at crank end dead center; Whereas, the spent orexhaust gases can discharge through an exhaust port 22 in the cylinderWall when uncovered by the piston 11. The movement of the piston to headend dead center as a result of rotation of the crankshaft 15 willcompress the combustible charge in the cylinder, which will then befired by a spark plug 23, or the like, mounted in the cylinder head 24,the piston being moved away from the cylinder head to uncover theexhaust port or ports 22 and the inlet port 21.

As specifically illustrated in the drawings, the crankcase includes aninduction case portion 25 containing a valve body 26 through which oneportion 19 of the crankshaft rotatably extends. The exterior of thisvalve body 26 is in spaced relation to the induction case 25 to providean annular passage 27 therebetween communicating with an inlet passage28 for the fuel-air mixture received from the engine carburetor 29. Thecarburetor is not disclosed specifically in FIGS. 1 to 5, but it isillustrated somewhat diagrammatically in FIGS. 6 to 9. Fuel from asuitable source can discharge from the carburetor jet 30 into the throatportion 31 of a venturi 32, air flowing through the venturi and drawingfuel from the carburetor jet 39 for admixture therewith, thiscombustible mixture then passing through the inlet 28 into the inductionpassage 27 and toward substantially diametrically opposed inlet ports 33of a transverse or flange portion 34 of the valve body 26 suitablyclamped between the induction case 25 and the main portion of thecrankcase 16, The combustible charge flows through the inlet ports 33into the crankcase .16 under the control of a one-Way feather or flappertype of valve element 35 of generally U or horseshoe shape, which isdisposed in the crankcase and which tends to seat against the valve body34 over its inlet ports 33 to prevent the combustible mixture frompassing back from the crankcase through the inlet ports 33 into theinduction passage 27.

As specifically disclosed, the feather valve element 35 has its centralor mid-portion 36 secured to the valve body flange 34 by a guard 37 ofgenerally U-shape, and

which overlies the feather valve element. As shown, the guard includes acentral clamp portion 38 having a recess,

pocket or tunnel 39 in which the mid-portion 36 of the feather valve isreceived. Suitable fastening elements 40, such as rivets, pass throughthe clamp portion 38 of the guard and through the mid-portion 36 of thefeather valve to secure such midportion to the valve body flange 34.

Opposed curved or arcuate arms 41 of the feather valve element 35 extendaround and on opposite sides of the crankshaft 15 in a positionoverlying the opposed inlet ports 33, which may also be arcuate inshape. The arms 41 extend beyond the ends of the inlet ports and alsoare substantially wider than the width of the ports so as to be capableof engaging the inner valve seating surface 34a of the valve body toclose the ports 33. The arms 42 of the guard overlie the arms 41 of thefeather valve, but are spaced outwardly from the inner surface 34a ofthe valve body flange 34 to permit movement of the feather valve arms 41away from the flange to open the inlet ports 33, the guard arms 42limiting the extent of movement of the feather valve arms so that theycan be acted upon by the pressure of the combustible charge in thecrankcase 16 for immediate closing against their companion valve seatingsurfaces 34a surrounding the inlet ports 33. Thus, the U- shaped guard37 serves the purpose of retaining the feather or flapper one-way valveelement 35 in place, of protecting it, and of limiting the extent of itsmovement away from its companion valve seats 34a surrounding the inletports 33.

As shown in FIG. 1, the piston 11 has moved to its crank end dead centerin which both the inlet and the exhaust ports 21, 22 are open. Thepiston then begins moving toward the cylinder head 24, and during suchupward movement it will decrease the pressure in the crankcase l6 andallow the pressure differential in the inlet and induction passage 27 toopen the feather valve 35 and draw a combustible charge into thecrankcase. When the piston 11 reaches substantially its head end deadcenter position, the spark plug 23 fires, igniting the combustiblecharge, the piston then being moved in the cylinder towards thecrankshaft 15. At the commencement of such downward stroke, thecombustible charge in the crankcase below the piston is compressed andcloses the feather valve 35 against its companion seat 34a to close theinlet ports 33. Continued movement of the piston then further compressesthe charge in the crankcase until the piston uncovers the exhaust port22, allowing the spent gases to exhaust therefrom, and also uncovers oropens the inlet port 21, allowing the compressed charge in the crankcase16 to flow through the inlet passage 26 into the cylinder. When thepiston 11 starts on its return stroke toward the head end 24 of thecylinder, it will again cover or close the inlet ports 21, creating asuction effect in the crankcase l6 and drawing a combustible charge fromthe inlet 23, through the induction passage 27 and inlet ports 33, thefeather valve 35 having moved away from its seat 34a to open position.

Heretofore, the feather valve element or reed valve element has beenmade of a relatively stiff thin steel, or similar metal, which normallytends to remain closed against its companion seat to close the inletport or ports. It is necessary for sufiicient suction to be developed inthe crankcase upon movement of the piston toward the head end of thecylinder to deflect the metal reed valve from its seat and draw thecombustible charge into the crankcase. The pressure developed in thecrankcase during the downstroke of the piston in the cylinder retainsthe metallic reed in closed position against its seat, and such closedposition remains until after the piston has reached its crank end deadcenter position. Because of the inherent tendency of the stiff, thinsteel reed to close against its companion seat, the amount ofcombustible charge entering the crankcase is reduced in view of thenecessity for first creating a certain suction in the crankcase toeffect opening of the valve. In addition, dirt or other foreign matterthat might settle on the seat or on the valve itself is clamped betweenthe valve and the companion seat and prevents full closing of the reedvalve. Moreover, because of the frequency of vibration of the steelvalve element, it becomes sensitive to the sonic waves in the engineitself, which adversely affects its proper functioning in that it maynot close against its seat at the time desired, may bounce from itsseat, and may remain closed against its seat for a greater period.

In the induction or inlet valve device illustrated in the drawings, thevalve element 35 inherently tends to assume an open position withrespect to its seat 34a, and it requires a pressure differential in thecrankcase 16 to move the valve element into engagement with its seat.The valve element is made of a material that is light, dead andsubstantially springless, having substantially no oscillation frequency.The valve element may be made of a soft pliable, light sheet material,such as rubber, leather, or a tetrafluoroethylene resin, marketed asTeflon. The valve element 35, made of a soft pliable, light sheetmaterial, has very little, if any, closing tension, tends to remain inopen position with respect to its valve seat 34a, and opens fully morereadily, as limited by its engagement with its protective guard 37. Suchmaterial, having substantially no oscillation frequency, closes as soonas the pressure in the crankcase rises, and does not vibrate.Consequently, it is not influenced by vibrations in the engine, but willmove into and from engagement with its seat Ma in strict accordance withthe positions of the piston 11 in its companion cylinder 1%. Moreover,when engaging the seat 3 30, it has no tendency to bounce therefrom, butwill remain closed thereagainst. In the event that any dirt particlestend to adhere to the seat 34a, the valve element 35 will deform aroundsuch particles and still effect its full closing against its seat 34a toprevent retrograde flow of any of the compressed fuel in the crankcasethrough the inlet ports 33. The fact that the valve element 35 normallytends to possess an open position when not subjected to the fluid pressure in the crankcase enables any dirt that might have been deposited onthe valve seat 34a, or on the face of the feather valve element 35itself, to be flushed or cleaned therefrom by the inflow of thecombustible charge through the inlet ports 33 and past the valve seatand the feather valve.

The feather valve element 35, which inherently tends to assume a valveopening position, enables the engine to operate in a much better manner,which, perhaps, can be best understood by reference to the diagrammaticviews illustrated in FIGS. 6 to 9, inclusive, of the drawings. Asdisclosed in FIG. 6, the piston 11 is on its compression stroke and hascreated a suction in the crankcase 16, in which the feather valve 35 iselevated from its seat 34a, or in open position, the combustible chargebeing drawn through the carburetor 29 and inlet passage 28 past the openfeather valve 35 into the crankcase. Upon the piston reaching its headend dead center position, the fuel charge in the cylinder is ignited todrive the piston 11 downwardly in the cylinder. As soon as the pistonbegins moving away from the cylinder head 24, pressure is developed inthe crankcase 16 which moves the feather or flapper valve 35 against itsseat 34a to close the inlet ports 33, the combustible charge previouslydrawn past the valve into the crankcase then being compressed (PEG. 7).Such compression will continue until the piston uncovers the exhaust andinlet ports 22, 21 of the cylinder, the spent gases passing outwardlythrough the exhaust port 22 and the pressurized combustible charge inthe crankcase 16 then passing upwardly through the inlet passage 20 andthe inlet port 21 into the cylinder above the piston.

As soon as the pressure in the crankcase 16 decreases sufficiently, thefeather valve 35 will open immediately, and this will occur as soon as,or slightly before, the piston 11 reaches crank end dead center, such asdisclosed in FIG. 8. In prior devices embodying relatively stiff, thinsteel reed valve elements that normally tend to remain closed againsttheir companion seat, the valve would only open after the piston 11 hasmoved upwardly to some extent on its suction stroke. In the presentcase, as the piston returns toward the Cylinder head 24 on itscompression stroke, the feather valve 35 is opened to its fullestextent, as limited by engagement with its guard 37, as illustrated inFIG. 9, to draw the combustible charge into the crankcase.

Because of the inherent characteristics of applicants feather valveelement 35, it will open at an earlier point in the cycle of operationof the engine, enabling a larger quantity of fuel to be drawn into thecrankcase 16 during movement of the piston 11 in the cylinder 10 towardits head end. This enables the engine to develop greater horsepower. Ithas also been found that the engine is easier to start and will idle atslower speeds. The feather valve 35 has a very low frequency ofvibration and is,

therefore, immune to adverse action with respect to its valve seat 34adue to the frequency of the engine, which can vary with the enginespeed. The lack of vibration in the flapper valve element itselfprevents it from fluttering with respect to its seat 34a and renders itimmune to sonic waves developed within the engine itself.

The opposed arms 41 of the feather or flapper valve element 35 are, ineffect, hingedly secured to its mid-portion 36, which is clamped againstthe valve body 34 by the guard 37. In view of the pliant material ofwhich the feather valve element 35 is made, it is disposed within thepocket 39 in the guard so that its mid-portion 36 cannot be adverselydeformed as a result of clamping the guard to the valve body flange 34by the rivets 40. The compression of the mid-portion 36 is limited byengagement of the guard portion 38 on opposite sides of the midportionof the valve element with the surface 34a of the flange 34.

I claim:

I. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body having an inlet adapted to communicate with thecrankcase, and a valve element constructed and arranged to normally andinherently tend to occupy a position opening said inlet in the absenceof a pressure differential acting thereon and adapted to be engaged withsaid valve body to close said inlet in response to com pression of thefuel mixture in the crankcase.

2. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body having an inlet adapted to communicate with thecrankcase, and a pliant, elastic valve element constructed and arrangedto normally and inherently tend to occupy a position opening said inletin the absence of a pressure differential acting thereon and adapted tobe engaged with said valve body to close said inlet in response tocompression of the fuel mixture in the crankcase.

3. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body having an inlet adapted to communicate with thecrankcase, and a valve element of tetrafluoroethylene sheet materialsecured to said valve body and constructed and arranged to normally andinherently tend to occupy a position opening said inlet in the absenceof a pressure differential acting thereon and adapted to be engaged withsaid valve body to close said inlet in response to compression of thefuel mixture in the crankcase.

4. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a Valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body through which said crankshaft extends and havinginlets on opposite sides of said crankshaft adapted to communicate withthe crankcase, and a valve element disposed on opposite sides of saidcrankshaft and constructed and arranged to normally and inherentlyoccupy a position opening said inlets in the absence of pressuredifferential acting thereon and adapted to be engaged with said bodyacross said inlets to close the same in response to compression of thefuel mixture in the crankcase.

5. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body through which said crankshaft extends and havinginlets on opposite sides of said crankshaft adapted to communicate withthe crankcase, and a pliant, elastic valve element having a centralportion and arm portions extending from said central portion on opposite sides of said crankshaft in overlying relation to said inlets,means securing said central portion to said valve body, said armportions being constructed and arranged to normally and inherentlyoccupy a position away from said valve body to open said inlets in theabsence of pressure differential acting thereon, said arm portions beingengaged with said body across said inlets to close the same in responseto compression of the fuel mixture in the crankcase.

6. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body through which said crankshaft extends and havinginlets on opposite sides of said crankshaft adapted to communicate withthe crankcase, and a valve element of tetrafiuoroethylene sheet materialhaving a central portion and arm portions extending from said centralportion on opposite sides of said crankshaft in overlying relation tosaid inlets, means ssecuring said central portion to said valve body,said arm portions being constructed and arranged to normally andinherently occupy a position away from said valve body to open saidinlets in the absence of pressure differential acting thereon, said armportions being engaged with said body across said inlets to close thesame in response to compression of the fuel mixture in the crankcase.

7. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body through which said crankshaft ex tends andhaving inlets on opposite sides of said crankshaft adapted tocommunicate with the crankcase, and a pliant, elastic valve elementhaving a central portion and arm portions extending from said centralportion on op posite sides of said crankshaft in overlying relation tosaid inlets, means securing said central portion to said valve bodycomprising a guard having a central portion provided with a recessreceiving said central portion of said element, said guard having armsoverlying said arm portions and spaced from said valve body, said armportions being constructed and arranged to normally and inherentlyoccupy a position away from said valve body to open said inlets in theabsence of pressure differential acting thereon, said arm portions beingengaged with said body across said inlets to close the same in responseto compression of the fuel mixture in the crankcase.

8. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body through which said crankshaft extends and havinginlets on opposite sides of said crankshaft adapted to communicate withthe crankcase, and a valve element of tetrafluoroethylene sheet materialhaving a central portion and arm portions extending from said centralportion on opposite sides of said crankshaft in overlying relation tosaid inlets, means securing said central portion to said valve bodycomprising a guard having a central portion provided with a recessreceiving said central portion of said element, said guard having armsoverlying said arm portions and spaced from said valve body, said armportions being constructed and arranged to normally and inherentlyoccupy a position away from said valve body to open said inlets in theabsence of pressure differential acting thereon, said arm portions beingengaged with said body across said inlets to close the same in responseto compression of the fuel mixture in the crankcase.

9. In a two-cycle internal combustion engine having a cylinder, acrankshaft, and a crankcase for said crankshaft adapted to receive afuel mixture for compression and transfer to the cylinder, a valvedevice controlling the induction of the fuel mixture into the crankcasecomprising a valve body having an inlet adapted to communicate with thecrankcase, a pliant, elastic valve element in overlying relation to saidinlet, means securing said valve element to said body comprising a guardhaving a recess receiving said element, said guard having a portionoverr lying said element and inlet and spaced from said valve body, saidvalve element being constructed and arranged to normally and inherentlytend to occupy a position opening said inlet in the absence of apressure differential acting thereon and adapted to be engaged with saidvalve body to close said inlet in response to compression of the 5 fuelmixture in the crankcase.

References Qited by the Examiner UNITED STATES PATENTS 1,029,726 6/12Sprado 1375l7 10 2,706,972 4/55 Kiekhaefer 123 73 2,779,576 1/157Morgenroth l23-73 FOREIGN PATENTS 487,498 4/18 France.

FRED E. ENGELTHALER, Primary Examiner.

1. IN A TWO-CYCLE INTERNAL COMBUSTION ENGINE HAVING A CYLINDER, ACRANKSHAFT, AND A CRANKCASE FOR SAID CRANKSHAFT ADAPTED TO RECEIVE AFUEL MIXTURE FOR COMPRESSION AND TRANSFER TO THE CYLINDER, A VALVEDEVICE CONTROLLING THE INDUCTION OF THE FUEL MIXTURE INTO THE CRANKCASECOMPRISING A VALVE BODY HAVING AN INLET ADAPTED TO COMMUNICATE WITH THECRANKCASE, AND A VALVE ELEMENT CONSTRUCTED AND ARRANGED TO NORMALLY ANDINHERENTLY TEND TO OCCUPY A POSITION OPENING SAID INLET IN THE ABSENCEOF A PRESSURE DIFFERENTIAL ACTING THEREON AND ADAPTED TO BE ENGAGED WITHSAID VALVE BODY TO CLOSE SAID INLET IN RESPONSE TO COMPRESSION OF THEFUEL MIXTURE IN THE CRANKCASE.